Compositions which can be stored under anhydrous conditions, but when exposed to atmospheric moisture crosslink to form elastomers at room temperature containing a diorganopolysiloxane, an organosilicon compound having at least three hydrolyzable groups bonded to the silicon atom per molecule and containing at least another substance are described in U.S. Pat. No. 4,230,826 to Sommer et al. The compositions described in the patent consist of (1) an organopolysiloxane having terminal condensable groups, (2) a silicon compound having at least 3 Si-bonded hydrolyzable groups per molecule and (3) a powder obtained from the homopolymerization or copolymerization of an acrylonitrile in an aqueous medium.
In contast to the elastomers described in U.S. Pat. No. 4,230,826, the elastomers of this invention have the advantage that they exhibit substantially better adhesion to synthetic substrates upon which they are formed than the elastomers known heretofore. Furthermore, the degree of adhesion of these elastomers is not dependent on the type of hydrolyzable groups present in the room temperature vulcanizable composition.
Therefore, it is an object of the present invention to provide organopolysiloxane compositions which exhibit improved adhesion properties. Another object of this invention is to provide room temperature vulcanizable compositions which will adhere to synthetic substrates. Still another object of the present invention is to provide organopolysiloxane compositions having non-slump properties. A further object of this invention is to provide elastomers whose degree of adhesion is not dependent on the hydrolyzable groups present in the composition.